Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6

X!Iinclude/linux/device.h

-->

!Edrivers/base/driver.c

!Edrivers/base/class_simple.c

!Edrivers/base/core.c

!Edrivers/base/firmware_class.c

!Edrivers/base/transport_class.c

platform_data: Platform data specific to the device.

	       Example:  for devices on custom boards, as typical of embedded

	       and SOC based hardware, Linux often uses platform_data to point

	       to board-specific structures describing devices and how they

	       are wired.  That can include what ports are available, chip

	       variants, which GPIO pins act in what additional roles, and so

	       on.  This shrinks the "Board Support Packages" (BSPs) and

	       minimizes board-specific #ifdefs in drivers.

current_state: Current power state of the device.

saved_state:   Pointer to saved state of the device. This is usable by

        char                    * name;

        struct bus_type         * bus;

        rwlock_t                lock;

        atomic_t                refcount;

        list_t                  bus_list;

        struct completion	unloaded;

        struct kobject		kobj;

        list_t                  devices;

        struct driver_dir_entry dir;

        struct module		*owner;

        int     (*probe)        (struct device * dev);

        int     (*remove)       (struct device * dev);

        int     (*suspend)      (struct device * dev, pm_message_t state, u32 level);

        int     (*resume)       (struct device * dev, u32 level);

        void    (*release)      (struct device_driver * drv);

};

static struct device_driver eepro100_driver = {

       .name		= "eepro100",

       .bus		= &pci_bus_type,

       .devclass	= &ethernet_devclass,	/* when it's implemented */

       .probe		= eepro100_probe,

       .remove		= eepro100_remove,

       .driver	       = {

		.name		= "eepro100",

		.bus		= &pci_bus_type,

		.devclass	= &ethernet_devclass,	/* when it's implemented */

		.probe		= eepro100_probe,

		.remove		= eepro100_remove,

		.suspend	= eepro100_suspend,

	int	(*probe)	(struct device * dev);

probe is called to verify the existence of a certain type of

hardware. This is called during the driver binding process, after the

bus has verified that the device ID of a device matches one of the

device IDs supported by the driver. 

This callback only verifies that there actually is supported hardware

present. It may allocate a driver-specific structure, but it should

not do any initialization of the hardware itself. The device-specific

structure may be stored in the device's driver_data field. 

	int	(*init)		(struct device * dev);

init is called during the binding stage. It is called after probe has

successfully returned and the device has been registered with its

class. It is responsible for initializing the hardware.

The probe() entry is called in task context, with the bus's rwsem locked

and the driver partially bound to the device.  Drivers commonly use

container_of() to convert "dev" to a bus-specific type, both in probe()

and other routines.  That type often provides device resource data, such

as pci_dev.resource[] or platform_device.resources, which is used in

addition to dev->platform_data to initialize the driver.

This callback holds the driver-specific logic to bind the driver to a

given device.  That includes verifying that the device is present, that

it's a version the driver can handle, that driver data structures can

be allocated and initialized, and that any hardware can be initialized.

Drivers often store a pointer to their state with dev_set_drvdata().

When the driver has successfully bound itself to that device, then probe()

returns zero and the driver model code will finish its part of binding

the driver to that device.

A driver's probe() may return a negative errno value to indicate that

the driver did not bind to this device, in which case it should have

released all reasources it allocated.

	int 	(*remove)	(struct device * dev);

remove is called to dissociate a driver with a device. This may be

remove is called to unbind a driver from a device. This may be

called if a device is physically removed from the system, if the

driver module is being unloaded, or during a reboot sequence. 

driver module is being unloaded, during a reboot sequence, or

in other cases.

It is up to the driver to determine if the device is present or

not. It should free any resources allocated specifically for the

A very simple (and naive) implementation of a device attribute is:

static ssize_t show_name(struct device * dev, char * buf)

static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf)

{

        return sprintf(buf,"%s\n",dev->name);

}

}

#define amba_attr(name,fmt,arg...)				\

static ssize_t show_##name(struct device *_dev, char *buf)	\

static ssize_t show_##name(struct device *_dev, struct device_attribute *attr, char *buf)	\

{								\

	struct amba_device *dev = to_amba_device(_dev);		\

	return sprintf(buf, fmt, arg);				\